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garlic

Pronunciation: GAR lick

What is the most important information I should know about garlic?

Garlic is a commonly used flavoring agent and food product. Garlic is also available as an herbal supplement. The information contained in this leaflet refers to the use of garlic as an herbal supplement. When used as a food product, the benefits and potential side effects of garlic may be less pronounced than when it is used as an herbal supplement.

Multum donot

Do not take garlic without first talking to your doctor if you have a bleeding or blood clotting disorder or diabetes, or if you are taking any medicines to prevent or treat a blood clotting disorder or diabetes. Garlic has been reported to affect blood clotting and blood sugar levels.

Garlic has not been evaluated by the FDA for safety, effectiveness, or purity. All potential risks and/or advantages of garlic may not be known. Additionally, there are no regulated manufacturing standards in place for these compounds. There have been instances where herbal/health supplements have been sold which were contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

What is garlic?

The use of garlic in cultural and traditional settings may differ from concepts accepted by current Western medicine. When considering the use of herbal supplements, consultation with a primary health care professional is advisable. Additionally, consultation with a practitioner trained in the uses of herbal/health supplements may be beneficial, and coordination of treatment among all health care providers involved may be advantageous.

Garlic is also known as rocambole, ajo, allium, stinking rose, rustic treacle, nectar of the gods, camphor of the poor, poor man's treacle, and clove garlic.

Garlic is a commonly used flavoring agent and food product. Garlic is also available as an herbal supplement. The information contained in this leaflet refers to the use of garlic as an herbal supplement. When used as a food product, the benefits and potential side effects of garlic may be less pronounced than when it is used as an herbal supplement.

Garlic has been used orally as an antioxidant; to reduce cholesterol and triglycerides; to reduce hardening of the arteries and blood clotting; to reduce blood pressure; to prevent cancer; to protect the liver; as an antibiotic, antiviral, and antifungal; to increase the effects of the immune system; to reduce blood sugar levels; and to reduce menstrual pain. Garlic has also been used topically (on the skin) to treat corns, warts, calluses, ear infections, muscle pain, nerve pain, arthritis, and sciatica.

Garlic has not been evaluated by the FDA for safety, effectiveness, or purity. All potential risks and/or advantages of garlic may not be known. Additionally, there are no regulated manufacturing standards in place for these compounds. There have been instances where herbal/health supplements have been sold which were contaminated with toxic metals or other drugs. Herbal/health supplements should be purchased from a reliable source to minimize the risk of contamination.

Garlic may also have uses other than those listed in this product guide.

What should I discuss with my healthcare provider before taking garlic?

Multum donot

Do not take garlic without first talking to your doctor if you have a bleeding or blood clotting disorder or diabetes, or if you are taking any medicines to prevent or treat a blood clotting disorder or diabetes. Garlic has been reported to affect blood clotting and blood sugar levels.

Also, talk to your doctor before taking garlic if you have any other medical conditions, if you take medicines or herbal/health supplements other than those previously listed, or if you suffer from allergies (especially to plants). Garlic may not be recommended in some situations.

Multum nopreg

Do not take garlic supplements without first talking to your doctor if you are pregnant or planning a pregnancy. It is not known whether garlic will harm an unborn baby. The amount of garlic customarily used in foods is not reported to be problematic.

Multum nobrfeed

Do not take garlic without first talking to your doctor if you are breast-feeding a baby. It is also not known whether garlic will harm a nursing infant. The amount of garlic customarily used in foods is not reported to be problematic.

There is no information available regarding the use of garlic supplements by children. Do not give any herbal/health supplement to a child without first talking to the child's doctor.

How should I take garlic?

The use of garlic in cultural and traditional settings may differ from concepts accepted by current Western medicine. When considering the use of herbal supplements, consultation with a primary health care professional is advisable. Additionally, consultation with a practitioner trained in the uses of herbal/health supplements may be beneficial, and coordination of treatment among all health care providers involved may be advantageous.

If you choose to take garlic, use it as directed on the package or as directed by your doctor, pharmacist, or other health care provider.

Standardized extracts, tinctures, and solid formulations of herbal/health supplements may provide a more reliable dose of the product.

Garlic is available in the clove form, in capsules, as tablets and as an oil. Other formulations may also be available.

Generally, the preferred forms of garlic for oral use are enteric-coated odorless garlic and fresh garlic which has been pressed or crushed for 10 to 15 minutes before using.

Multum donot

Do not use different formulations (e.g., tablets, topical formulations, teas, tinctures, and others) of garlic at the same time, unless specifically directed to do so by a health care professional. Using different formulations together increases the risk of an overdose of garlic.

Store garlic as directed on the package. In general, garlic should be protected from light and moisture.

What happens if I miss a dose?

No information is available regarding a missed dose of garlic. Consult your doctor, pharmacist, or health care provider if you require further information.

What happens if I overdose?

An overdose of garlic is unlikely to threaten life. Consult a doctor, hospital, or poison control center if you require assistance.

Symptoms of a garlic overdose have not been reported.

What should I avoid while taking garlic?

There are no known restrictions on food, beverages, or activity while taking garlic, unless otherwise directed by your health care provider.

What are the possible side effects of garlic?

Multum emt

Although uncommon, allergic reactions to garlic have been reported. Stop taking garlic and seek emergency medical attention if you experience symptoms of a serious allergic reaction including difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives.

Other less serious side effects have also been reported. Talk to your doctor or pharmacist if you experience

  • burning of the mouth, throat, and stomach;
  • nausea or vomiting;
  • diarrhea;
  • sweating;
  • lightheadedness; and
  • eczema or a rash.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect garlic?

Multum donot

Do not take garlic without first talking to your doctor if you are taking any of the following medicines:

  • a medicine to control blood sugar levels such as insulin, glipizide (Glucotrol), glyburide (Glynase, Diabeta, Micronase), chlorpropamide (Diabinese), tolbutamide (Orinase), tolazamide (Tolinase), pioglitazone (Actos), rosiglitazone (Avandia), repaglinide (Prandin), metformin (Glucophage), and others;
  • a nonsteroidal anti-inflammatory drug (NSAID) including ibuprofen (Advil, Motrin, Nuprin, others), naproxen (Aleve, Naprosyn, Naprelan, Anaprox, others), ketoprofen (Orudis KT, Orudis), indomethacin (Indocin), etodolac (Lodine), nabumetone (Relafen), oxaprozin (Daypro), piroxicam (Feldene), sulindac (Clinoril), tolmetin (Tolectin), and others;
  • a protease inhibitor such as amprenavir (Agenerase), indinavir (Crixivan), saquinavir (Invirase, Fortovase), lopinavir-ritonavir (Kaletra), ritonavir (Norvir), or nelfinavir (Viracept);
  • ardeparin (Normiflo), dalteparin (Fragmin), danaparoid (Orgaran), enoxaparin (Lovenox), tinzaparin (Innohep);
  • warfarin (Coumadin);
  • aspirin; or
  • heparin.

You may not be able to take garlic, or you may require a dosage adjustment or special monitoring while taking garlic if you are taking any of the medicines listed above.

Drugs other than those listed here may also interact with garlic or affect your condition. Talk to your doctor, pharmacist, or health care provider before taking any prescription or over-the-counter medicines or other herbal/health supplements.

Where can I get more information?

Your doctor, pharmacist, or health care provider may have more information about garlic.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

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